I Love my SP101, .357 magnum.
I have used mine for every day, CCW, for about 7 years. It is not a 3" but a 2.25". I carry it in a Galco open top, S/S, high-ride pancake holster.
I have never carried .38 specials in mine. Although I have used them for practice a couple times. It's a .357 magnum. So, that's what I carry.
I've used everything from 110 gr. SJLHP's to 158 gr. JHP's. Even a 110 gr.
.357 magnum is better than a .38 special, AISI.
Honestly, I live rural, and the only thing I've ever killed is a 4' copperhead snake. A 110 gr. HP blew that snake it two.
Oh, and I ran across a 2nd one in great shape, so, I bought it for a spare, JIC. My DSW shoots it just fine too.
Have fun!